square sail


: a 4-sided sail extended on a yard suspended at the middle from a mast

Example Sentences

Recent Examples on the Web After three days in space, giving the miniature satellite time to get away from FASTSAT, NanoSail-D was supposed to deploy its fragile cargo: a square sail, 10 meters by 10 meters and made of a whisper-thin reflective polymer. Elizabeth Preston, Discover Magazine, 16 Dec. 2010 At the same time, the vessel may have had a single mast with a square sail, similar to a Viking ship. Sarah Kuta, Smithsonian Magazine, 28 Nov. 2022 According to Bill Nye, the advent of CubeSats actually led to the current square sail design. Amy Thompson, Smithsonian, 25 June 2019 After seven days in space, LightSail 2 will pop out of its container, extend four long booms, and deploy four sheets of mirror-like Mylar plastic into a 340-square-foot, square sail. NBC News, 3 June 2019 When the wind blew favorably, the crew would have hoisted a square sail on the mast; the rest of the time, rowers would have lined up on the benches and propelled the ship along with large oars. Kiona N. Smith, Ars Technica, 24 Oct. 2018

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'square sail.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1600, in the meaning defined above

Time Traveler
The first known use of square sail was in 1600

Dictionary Entries Near square sail

Cite this Entry

“Square sail.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/square%20sail. Accessed 6 Jun. 2023.

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